• Proceedings of the KIEE Conference
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• 1994.07b
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• pp.1223-1225
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• 1994

The properties of $TiN/TiSi_2$ bilayer formed by a rapid thermal anneal ing is investigated when thin $SiO_2$ film exists at the Ti-Si interface. The competitive reaction for the $TiN/TiSi_2$ bilayer occurs above $600^{\circ}C$. The thickness of the $TiSi_2$ layer decreases with increasing $SiO_2$ film thickness while the TiN layer increases at the competitive reaction. The composition of TiN layer is changed to the $TiN_xO_y$ film due to the thin $SiO_2$ layer at the Ti-Si interface while the structure of the TiN and $TiSi_2$ layers was not changed.

• Advances in materials Research
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• v.6 no.3
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• pp.245-255
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• 2017

High energy ball milling is employed to produce iron matrix- multiwall carbon nanotube (MWCNT) reinforced composite. The damage caused to MWCNT due to harsh ball milling condition and its influence on interfacial bonding is studied. Different amount of MWCNT is used to find the optimal percentage of MWCNT for avoidance of the formation of chemical reaction product at the matrix - reinforcement interface. Effect of process control agent is assessed by the use of different materials for the purpose. It is observed that ethanol as a process control agent (PCA) causes degradation of MWCNT reinforcements after milling for two hours whereas solid stearic acid used as process control agent, allows satisfactory conservation of MWCNT structure. It is further noted that at a high MWCNT content (~ 2wt.%), high energy ball milling leads to reaction of iron and carbon and forms iron carbide (cementite) at the iron-MWCNT interface. At low percentage of MWCNT, dissolution of carbon in iron takes place and the amount of reinforcement in iron matrix composite becomes negligibly small. However, under the present ball milling condition (ball to metal ratio~ 6:1 and 200 rpm vial speed) iron-1wt.% MWCNT composite of good interfacial bonding can retain the tubular structure of reinforcing MWCNT.

• Journal of Adhesion and Interface
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• v.25 no.1
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• pp.152-156
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• 2024

We conducted research on a two-component epoxy adhesive material based on acid graft polyolefin using maleic anhydride to address the lack of formability due to epoxy adhesives' hard segments. To understand the graft efficiency according to reaction conditions, we conducted studies based on polyolefin molecular weight, initiator half-life, and initiator concentration for each process. The maleic anhydride grafted polyolefin produced was used as an adhesive material for aluminum and CPP film lamination after mixing with epoxy hardener. The graft efficiency in the solution process was approximately 30% superior to that in the melt process, and an increase in graft ratio confirmed an increase in peel strength.

• The Journal of the Korea Contents Association
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• v.22 no.6
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• pp.307-318
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• 2022

Virtual reality is actively used in the medical field as a learning effectiveness that induces immersion, but research on the factors that induce learning immersion is insufficient. Therefore, this study extracted the usability and cognitive affordance evaluation elements of the interface through literature research and selected four types of virtual reality medical contents to conduct a Useability-Test for experts. Based on this, an interface design method according to virtual reality medical technology content was proposed. In summary, it can be seen that the information-providing interface affects immersion due to visibility, distance from the experience's gaze, color harmony, uniform visualization, feedback, reaction speed, and expected changes resulting from manipulation, and does not impair immersion. This study has limitations in generalization using limited content, so it is expected that continuous research will discuss the development of standardized guides in interface design and the precision of interface design research from a user perspective.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.246-246
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• 2012

Smart catalyst design though novel catalyst preparation methods can improve catalytic activity of transition metals on reducible oxide supports such as titania by enhancement of metal oxide interface effects. In this work, we investigated Pt nanoparticles/titania catalysts under CO oxidation reaction by using novel preparation methods in order to enhance its catalytic activity by optimizing metal oxide interface. Arc plasma deposition (APD) and metal impregnation techniques are employed to achieve Pt metal deposition on titania supports which are prepared by multi-target sputtering and Sol-gel techniques. In order to tailor metal-support interface for catalytic CO oxidation reaction, Pt nanoparticles and thin films are deposited in varying surface coverages on sputtered titania films using APD. To assess the role of oxide support at the interface, APD-Pt is deposited on sputtered and Sol-gel prepared titania films. Lastly, characteristics of APD-Pt process are compared with Pt impregnation technique. Our results show that activity of Pt nanoparticles is improved when supported over Sol-Gel prepared titania than sputtered titania film. It is suggested that this enhanced activity can be partly ascribed to a very rough titania surface with the higher free metal surface area and higher number of sites at the interface between the metal and the support. Also, APD-Pt shows superior catalytic activity under CO oxidation as compared to Pt impregnation on sputtered titania support. XPS results show that bulk oxide is formed on Pt when deposited through impregnation and has higher proportion of oxidized Pt in the form of $Pt^{2+/4+}$ oxidation states than Pt metal. APD-Pt shows, however, mild oxidation with large proportion of active Pt metal. APD-Pt also shows trend of increasing CO oxidation activity with number of shots. The activity continues to increase with surface coverage beyond 100%, thus suggesting a very rough and porous Pt films with higher active surface metal sites due to an increased surface area available for the reactant CO and $O_2$ molecules. The results suggest a novel approach for systematic investigation into metal oxide interface by rational catalysts design which can be extended to other metal-support systems in the future.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.350-350
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• 2006

We investigated, via atomic force microscopy and transmission electron microscopy, the effect of shear force on the interfacial morphology of a reactive bilayer polymer system composed of PS-mCOOH and PMMAGMA. It has been observed that in the absence of oscillatory shearing the roughness of the interface increased with reaction period, while at large values of ${\gamma}_{0}\;and\;{\omega}$ it became less than that observed in the absence of oscillatory shearing. This observation may be attributable to the possibility that oscillatory shearing might have hindered the diffusion of polymer chains, which are located away from the interface, to the interface of the layers. However, the effect of ${\gamma}_{0}\;and\;{\omega}$ on the roughness of the interface of (PS-mCOOH)/(PMMA-GMA) bilayer is found to be quite different.

• Journal of Electrochemical Science and Technology
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• v.9 no.3
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• pp.176-183
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• 2018

In this study, a $Li_2ZrO_3$ coated $Li[Ni_{0.8}Co_{0.15}Al_{0.05}]O_2$ (NCA) cathode was applied to an all-solid-state cell employing a sulfide-based solid electrolyte. Sulfide-based solid electrolytes are preferable for all-solid-state cells because of their high ionic conductivity and good softness and elasticity. However, sulfides are very reactive with oxide cathodes, and this reduces the stability of the cathode/electrolyte interface of all-solid-state cells. $Li_2ZrO_3$ is expected to be a suitable coating material for the cathode because it can suppress the undesirable reactions at the cathode/sulfide electrolyte interface because of its good stability and high ionic conductivity. Cells employing $Li_2ZrO_3$ coated NCA showed superior capacity to those employing pristine NCA. Analysis by X-ray photoelectron spectroscopy and electron energy loss spectroscopy confirmed that the $Li_2ZrO_3$ coating layer suppresses the propagation of S and P into the cathode and the reaction between the cathode and the sulfide solid electrolyte. These results show that $Li_2ZrO_3$ coating is promising for reducing undesirable side reactions at the cathode/electrolyte interface of all-solid-state-cells.

• Journal of the Korea Computer Industry Society
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• v.5 no.2
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• pp.217-226
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• 2004

This paper proposes the electric stimulus tactile apparatus system(TESTAS) loaded on the haptic interface using ultrasonic motors (USMs) To touch the virtual object like wall in graphic, the 6 DOF haptic interface provides force feedback to users as if it is real. But the case of sharp virtual object like a puncture, it could not provided the sense of pain, but only the reaction-force. After the TESTAS had been loaded on this haptic interface, it could provide not only the force but also the pain to users. In this way, when users take the haptic and tactile informations at the same time, they easily have a correct understanding of virtual object.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.08a
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• pp.72-72
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• 2010

Recent development of organic solar cell approaches the level of 8% power conversion efficiency by the introduction of new materials, improved material engineering, and more sophisticated device structures. As for interface engineering, various interlayer materials such as LiF, CaO, NaF, and KF have been utilized between Al electrode and active layer. Those materials lower the work function of cathode and interface barrier, protect the active layer, enhance charge collection efficiency, and induce active layer doping. However, the addition of another step of thin layer deposition could be a little complicated. Thus, on a typical solar cell structure of Al/P3HT:PCBM/PEDOT:PSS/ITO glass, we used Li:Al alloy electrode instead of Al to render a simple process. J-V measurement under dark and light illumination on the polymer solar cell using Li:Al cathode shows the improvement in electric properties such as decrease in leakage current and series resistance, and increase in circuit current density. This effective charge collection and electron transport correspond to lowered energy barrier for electron transport at the interface, which is measured by ultraviolet photoelectron spectroscopy. Indeed, through the measurement of secondary ion mass spectroscopy, the Li atoms turn out to be located mainly at the interface between polymer and Al metal. In addition, the chemical reaction between polymer and metal electrodes are measured by X-ray photoelectron spectroscopy.

• Proceedings of the KIPE Conference
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• 2001.07a
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• pp.9-13
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• 2001

This paper proposes the electric stimulus tactile apparatus system(TESTAS) loaded on the hap-tic interface using ultrasonic motors(USMs). To touch the virtual object like wall in graphic, the 6 DOF haptic interface provides force feedback to users as if it is real. But the case of sharp virtual object like a puncture, it could not provided the sense of pain, but only the reaction-force. After the TESTAS had been loaded on this haptic interface. it could Provide not only the force but also the pain to users. To estimate the capability of TESTAS, we did experiments of three cases, one was very sharp, another was dull, the other is continuative contact.